The present invention relates to container closures having liners designed to seal open containers, and particularly, to a closure liner arrangement having an enlarged pull tab which facilitates opening of the container.
Aluminum or metallic foil seals are in common use for sealing the mouths of bottles, especially bottles containing consumable products such as pharmaceuticals, food products, etc. In such applications, the foil seal is adhered to the mouth of the bottle subsequent to the filling thereof with the desired consumable product in question. These common seals accomplish two important functions, i.e., they first serve to ensure that no foreign material has entered the bottle after it has been filled with the intended product, and, secondly, they serve to prevent purposeful tampering, because access to the interior of the bottle cannot be achieved without destroying the seal.
These aluminum foil seals are available in a number of forms, including foil coated with polymer, and polymer coated foil laminated to paper. The polymer coating serves to facilitate adherence of the seal to the mouth of the bottle through the application of heat. The bottles most commonly used are plastic bottles, although it is also possible to use a glass bottle with a polymer coated neck end. Such seals are also available which are coated with a special polymer which will even adhere to uncoated glass.
A major problem of conventional seals is that they are extremely difficult for the consumer to remove from the mouth of the bottle. Often there is nothing for the consumer to grab in attempt to remove the seal. Consequently, the consumer usually must use a potentially dangerous sharp tool such as a knife, or merely pokes a finger through the seal. This in turn results in a second problem, i.e., the flexible aluminum seal is not completely removed from the edge of the bottle neck, and is therefore ragged around the opening, making it difficult to remove the product.
Solutions have been proposed, including the formation of gripping tabs along the edge of the seal which project outwardly or vertically beyond the neck of the bottle to facilitate removal of the seal through grasping by the user.
U.S. Pat. No. 4,754,890 discloses a container seal formed from a seal liner having an integral tab portion, the tab being double-folded in a "Z" shape for increased strength and to prevent adherence of the tab to a cap liner. When the container cap is removed, the user unfolds the tab portion to remove the seal. A disadvantage of the seal of the '890 patent is that the tab is still not large enough to facilitate easy opening by consumers.
Thus, there is a need for a container closure liner having a pull tab which is large enough to allow a consumer to grasp and totally remove the seal liner from the container opening. The closure liner should be easy to manufacture and assemble and inexpensive to produce.